LOCHINVAR ENJB-40 1**

The registry does not list the 3,456 kWh figure. This site computed it from the registry's UEF, the ratio of hot water delivered to energy used, and the DOE test's daily hot-water draw for the medium pattern. This model's UEF is 0.94. The medium pattern stands for a typical household of several people, with a busy morning of hot-water use. If your household draws more or less hot water than the test assumes, your yearly use will differ from 3,456 kWh. The registry data behind the figure comes from the DOE CCD, retrieved 2026-09-19. Each step of the calculation is set out on the page explaining how the annual energy and cost figures are calculated.

The tank has a rated volume of 35 gallons. Its first hour rating, the gallons of hot water available in the first hour from a full tank, is 57 gallons. These two ratings describe a household whose use matches the medium draw pattern. A household that often needs more than 57 gallons in its busiest hour needs more than this rating covers. Within its class, the model sits 75 kWh below the median of 3,531 kWh a year under the same test. At 137th lowest of 426, other models in the same class use less energy at this draw pattern. To compare models of the same class, use the same-class replacement search by model number.

Running cost is not stated in this text. It depends on your own utility's electricity tariff, and that tariff differs from one home to another. The page computes the cost from your ZIP, applying your rate to the 3,456 kWh yearly use at the medium draw pattern. The water heater cost calculator for your own ZIP shows that result. The 75 kWh gap to the class median is an energy difference at the federal test's draw. What that gap costs you a year also depends on your rate, so it is not given here. The installed-price block on this page is a modeled range with its own source and date, not a quote.